Reacción a "A study involving mice and humans suggests that a bacterial supplement could improve female fertility"

This study offers a novel perspective on reproductive ageing by focusing on the role of the endometrium and its microbiota, an aspect that has been much less studied than ovarian ageing. The authors show that the abundance of Lactobacillus gasseri decreases with age and that a higher presence of bacteria of the genus Lactobacillus is associated with better outcomes following embryo transfer. Furthermore, through studies using cell cultures and animal models, they identify a possible biological mechanism by which postbiotics derived from L. gasseri could improve endometrial receptivity.

This is a study of high methodological quality, as it combines clinical observations with functional studies that help to understand the mechanisms involved. The results are consistent with the growing evidence suggesting that the endometrial microbiota may influence embryo implantation and expand our understanding of the possible role of the endometrium in reproductive ageing. However, it is important to note that the clinical part of the study demonstrates an association between microbiota composition and reproductive outcomes, but does not allow a causal relationship to be established. Furthermore, although the authors use different experimental approaches to support their conclusions, the beneficial effects of postbiotics have mainly been demonstrated in animal models; therefore, they cannot yet be directly extrapolated to clinical practice.

Another significant limitation is that the study includes a relatively small number of patients, all of whom were undergoing treatment for infertility, which may limit the generalisability of the results. Furthermore, reproductive ageing is a complex, multifactorial process involving numerous biological factors, so the endometrial microbiota likely represents only one part of the process.

Overall, this study makes an important contribution to a better understanding of the changes the endometrium undergoes with age and opens up a very promising line of research into the potential use of postbiotics to improve endometrial receptivity. However, before any clinical application can be considered, prospective studies and clinical trials will be needed to confirm both the efficacy and safety of these interventions in women.